/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the  "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id$
 */
package wx.xml.xalan.xml.res;

import java.util.ListResourceBundle;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

/**
 * A utility class for issuing XML error messages.
 *
 * @xsl.usage internal
 */
public class XMLMessages {

    /**
     * String to use if a bad message code is used.
     */
    protected static final String BAD_CODE = "BAD_CODE";
    /**
     * String to use if the message format operation failed.
     */
    protected static final String FORMAT_FAILED = "FORMAT_FAILED";
    /**
     * The class name of the XML error message string table.
     */
    private static final String XML_ERROR_RESOURCES =
        "wx.xml.xalan.xml.res.XMLErrorResources";
    /**
     * The language specific resource object for XML messages.
     */
    private static ListResourceBundle XMLBundle = null;
    /**
     * The local object to use.
     */
    protected Locale fLocale = Locale.getDefault();

    /**
     * Creates a message from the specified key and replacement
     * arguments, localized to the given locale.
     *
     * @param msgKey The key for the message text.
     * @param args   The arguments to be used as replacement text
     *               in the message created.
     * @return The formatted message string.
     */
    public static final String createXMLMessage(String msgKey, Object args[]) {
        if (XMLBundle == null)
            XMLBundle = loadResourceBundle(XML_ERROR_RESOURCES);

        if (XMLBundle != null) {
            return createMsg(XMLBundle, msgKey, args);
        } else
            return "Could not load any resource bundles.";
    }

    /**
     * Creates a message from the specified key and replacement
     * arguments, localized to the given locale.
     *
     * @param fResourceBundle The resource bundle to use.
     * @param msgKey          The message key to use.
     * @param args            The arguments to be used as replacement text
     *                        in the message created.
     * @return The formatted message string.
     */
    public static final String createMsg(ListResourceBundle fResourceBundle,
                                         String msgKey, Object args[])  //throws Exception
    {

        String  fmsg    = null;
        boolean throwex = false;
        String  msg     = null;

        if (msgKey != null)
            msg = fResourceBundle.getString(msgKey);

        if (msg == null) {
            msg = fResourceBundle.getString(BAD_CODE);
            throwex = true;
        }

        if (args != null) {
            try {

                // Do this to keep format from crying.
                // This is better than making a bunch of conditional
                // code all over the place.
                int n = args.length;

                for (int i = 0; i < n; i++) {
                    if (null == args[i])
                        args[i] = "";
                }

                fmsg = java.text.MessageFormat.format(msg, args);
            } catch (Exception e) {
                fmsg = fResourceBundle.getString(FORMAT_FAILED);
                fmsg += " " + msg;
            }
        } else
            fmsg = msg;

        if (throwex) {
            throw new RuntimeException(fmsg);
        }

        return fmsg;
    }

    /**
     * Return a named ResourceBundle for a particular locale.  This method mimics the behavior
     * of ResourceBundle.getBundle().
     *
     * @param className The class name of the resource bundle.
     * @return the ResourceBundle
     * @throws MissingResourceException
     */
    public static ListResourceBundle loadResourceBundle(String className)
        throws MissingResourceException {
        Locale locale = Locale.getDefault();

        try {
            return (ListResourceBundle) ResourceBundle.getBundle(className, locale);
        } catch (MissingResourceException e) {
            try  // try to fall back to en_US if we can't load
            {

                // Since we can't find the localized property file,
                // fall back to en_US.
                return (ListResourceBundle) ResourceBundle.getBundle(
                    className, new Locale("en", "US"));
            } catch (MissingResourceException e2) {

                // Now we are really in trouble.
                // very bad, definitely very bad...not going to get very far
                throw new MissingResourceException(
                    "Could not load any resource bundles." + className, className, "");
            }
        }
    }

    /**
     * Return the resource file suffic for the indicated locale
     * For most locales, this will be based the language code.  However
     * for Chinese, we do distinguish between Taiwan and PRC
     *
     * @param locale the locale
     * @return an String suffix which can be appended to a resource name
     */
    protected static String getResourceSuffix(Locale locale) {

        String suffix  = "_" + locale.getLanguage();
        String country = locale.getCountry();

        if (country.equals("TW"))
            suffix += "_" + country;

        return suffix;
    }

    /**
     * Get the Locale object that is being used.
     *
     * @return non-null reference to Locale object.
     */
    public Locale getLocale() {
        return fLocale;
    }

    /**
     * Set the Locale object to use.
     *
     * @param locale non-null reference to Locale object.
     */
    public void setLocale(Locale locale) {
        fLocale = locale;
    }
}
